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    <title>Document</title>
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<script>
    (function () {
        function compileStr(code) { //对字符串进行加密
            var c = String.fromCharCode(code.charCodeAt(0) + code.length);
            for (var i = 1; i < code.length; i++) {
                c += String.fromCharCode(code.charCodeAt(i) + code.charCodeAt(i - 1));
            }
            return escape(c);
        }
        //字符串进行解密
        function uncompileStr(code) {
            code = unescape(code);
            var c = String.fromCharCode(code.charCodeAt(0) - code.length);
            for (var i = 1; i < code.length; i++) {
                c += String.fromCharCode(code.charCodeAt(i) - c.charCodeAt(i - 1));
            }
            return c;
        }
        var str = '1234568'
        console.log(compileStr(str));
    })();
</script>

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